Already the subject of a documentary, and now the centre of a big-budget Hollywood film, former convict Richard Wershe, Jr. boasts one of those stories so outrageous that it has to be true. These things should tell themselves, right? But alas, the middling White Boy Rick proves that’s not the case.

It’s the 1980s, and the son of a Detroit petty criminal gets in tight with the local drug thugs while working covertly with law enforcement. When everything collapses in spectacular fashion, the then-17-year-old Wershe, Jr. is sentenced to life in prison under Michigan’s since-repealed 650 Lifer Law for possessing eight kilos of cocaine, despite being a juvenile — and a non-violent one at that — plus helping the cops. He’d spend nearly 30 years behind bars before being released in 2017.

White Boy Rick ends as Wershe Jr. enters prison; we hear from the real guy in voice-over at film’s close. And honestly, it’s tempting to think the adult Wershe Jr. might have some pretty pertinent things to say about America’s twin but contrary obsessions with money and virtue, the key accelerants to his criminality.

The story leading up to his incarceration is a wan illustration of the decaying of a corrupt and perennially snowy Detroit, where cops and other government officials are as dodgy as the mullet sported by Matthew McConaughey playing Richard Wershe Sr., a loving if deeply misguided father whose other dubious claim to fame is having a drug-addicted daughter, played by Bel Powley.

But here’s the thing: it’s hard to care about anyone presented on screen. Sorry but… they’re just not very nice. Nor are they fascinating criminal masterminds pulling off complex, game-changing capers.

McConaughey pretty much owns White Boy Rick. There’s no shame in that for young actor Richie Merritt in the title role who wears the ridiculous hair and peach fuzz of an 80s-era teenager with aplomb but can’t hope to out-scumbag a co-star who has been essaying that role since 1993’s Dazed and Confused.

White Boy Rick invites us to once again shake our heads at the futility of the so-called American War on Drugs, which at this point is akin to saying smoking cigarettes might be unhealthy. We get it. I ask again: are we invested in the characters as people? Even Jennifer Jason Lee — as the dour cop on Wershe Jr.’s tail and possibly channeling Dorothy Parker from a previous movie— seems thoroughly bored by the various goings-on.

And really, why would anyone want to cheer for a kid who, when not dealing drugs — and he need only look at his sister to see what that nefarious activity brings — is squealing about it to the cops?